Read and execute a text file in Bash

adrianadonis · 07-16-2012, 04:24 PM

I need a bash script that uses a text file of parameters. It will use groups of five lines at a time. Line 1 is test name. Line 2 and Line 3 is a command that i need to execute. Line 4 is a model file. And line 5 is a redirect file. I need to execute line 2, then execute line 3 and redirect the output to the file that is line 5, finally it has to compare the output and the redirect file. Then go through all that again til it runs out of groups of five.

I'm not very good at scripting so any help you can give me would be great.
Thank you.

EDIT: Can a mod move this post to programming?

corp769 · 07-16-2012, 04:28 PM

Awk sounds like what you are looking for, first of all. On a side note though, could you post us an example text file? And what do you have so far of your script?

adrianadonis · 07-16-2012, 04:42 PM

here is an example of a test file:

Code:

testname
echo "this is the first command"
echo "this is the second command"
ModelFileName
OutputFilename
testname2
...

Also I just started to learn bash so anything you can give me to help me start off would be appreciated.

sharadchhetri · 07-16-2012, 05:24 PM

Quote:

Originally Posted by adrianadonis

here is an example of a test file:

Code:

testname
echo "this is the first command"
echo "this is the second command"
ModelFileName
OutputFilename
testname2
...

Also I just started to learn bash so anything you can give me to help me start off would be appreciated.

sed -n '2p' filename

this command will help you to get the line no. 2 from file. I will give you some basic idea.I hope it will help you.
for eg.

#!/bin/bash

x=`sed -n '2p' filename`
y=`sed -n '3p' filename`

echo "below is command-1,line no.2 output" >> OutputFilename
$x >> OutputFilename
echo "below is command-2,line no.3 output" >> OutputFilename
$y >> OutputFilename

And you can see the result by this

Quote:

cat OutputFilename

grail · 07-16-2012, 08:13 PM

Is the data contained in the file something you are creating? If it is, my suggestion would be to remove the echo commands and leave the lines
on their own to be echoed within your script.

chrism01 · 07-16-2012, 08:25 PM

Here are some good bash links
http://rute.2038bug.com/index.html.gz
http://tldp.org/LDP/Bash-Beginners-G...tml/index.html
http://www.tldp.org/LDP/abs/html/

awk & sed
http://www.grymoire.com/Unix/

adrianadonis · 07-17-2012, 01:10 PM

Quote:

Originally Posted by grail

Is the data contained in the file something you are creating? If it is, my suggestion would be to remove the echo commands and leave the lines
on their own to be echoed within your script.

the echo is just an example the actual command is a command executed by another program.

sharadchhetri · 07-17-2012, 04:10 PM

Quote:

Originally Posted by adrianadonis

the echo is just an example the actual command is a command executed by another program.

the eg. I gave is it useful

grail · 07-18-2012, 02:42 AM

Quote:

the echo is just an example the actual command is a command executed by another program.

The general rule of thumb with scripting is to place data in variables and use functions for execution.

If the file must maintain the current format I would probably extract the line and then check the first word(s) in a case or if clause (depending on number of options)
and then call the actual command with the remainder of the line.

So maybe something like:

Code:

#!/bin/bash

mapfile -t lines < test_file

(( n_lines =  ${#lines[*]} % 5 ))

for (( i = 0; i < n_lines; i++ ))
do
    commands=( ${lines[i*5+1]%% *} ${lines[i*5+2]%% *} )

    for (( j = 0; j < 2; j++))
    do
        if [[ ${commands[j]} == echo ]]
        then
            echo "${lines[i*5+j+1]#* }" >> ${lines[i*5+4]}
        fi
    done
done

adrianadonis · 07-20-2012, 04:12 PM

Thanks for everyone's help I finally have a working bash script. I'm going to post it here if anyone has any comments on it I would like to hear them.

Code:

#!/bin/bash

rm -rf results/*

rm -rf dif/*





# Load text file lines into a bash array.

OLD_IFS=$IFS

IFS=$'\n'

lines_ary=( $(cat "./real.txt") )

IFS=$OLD_IFS



output= $1 





idx=0

function check {
	if [ $char_1 = '#' ]
		let idx=idx+1

	fi
}


# Print each line in the array.

while [ $idx -lt $((${#lines_ary[@]} - 1)) ];

do   
	Char_1= ${lines_ary[@]:0:1}
	if [ $char_1 != '#' ]

 	then
		testname="${lines_ary[$idx]}"

		let idx=idx+1
		check

		testcmd="${lines_ary[$idx]}"

		let idx=idx+1
		check

		outputcmd="${lines_ary[$idx]}"

		let idx=idx+1
		check

		outputfilename=$testname".result"

		modelfilename=$testname".model"

		difffilename=$testname".dif"

		printf "executing testcmd" "${testname}\n"	

		$testcmd

		$outputcmd>>./results/$outputfilename

		diff -q ./results/$outputfilename ./models/$modelfilename>>./dif/$difffilename

		if [[ $? == "0" ]]

		then

			echo -e " \e[00;32mPASS\e[00m"

		else

			echo -e " \e[00;31mFAIL\e[00m"

		fi
	else
		let idx=idx+1
	fi

done